import java.util.Scanner;

public class Main1830 {
    public static void main(String[] args) {
        Scanner sc=new Scanner(System.in);
        int n=sc.nextInt();
        int [] arr=new int[n];
        for (int i=0;i<arr.length;i++){
            arr[i]=sc.nextInt();
        }
        int a=0;
        for (int i=0;i< arr.length;i++){
            a=a+arr[i]*arr[i];
        }
        System.out.println(a);
    }
}
